1. Field of the Invention
The present invention relates to a radio beacon for a nautical emergency rescue system.
2. Description of the Prior Art
Recent years have seen a dramatic increase in the number of pleasure craft using coastal waters. Sailing and power boating have become the hobbies of many. But the pleasure of sailing can rapidly turn to disaster in the event of capsize, of becoming lost in the fog, or of being disabled in a storm, to name only a few dangers of the sea. In these events, help may not always be near. Impaired visibility due to bad weather is more the rule than the exception. Two-way radio provides the means for summoning help, but is relatively expensive and thus not available to the majority of boat owners.
The present invention relates to a system for summoning aid to a vessel in distress. To this end, each sail boat or power boat is provided with a compact radio beacon transmitter contained in a waterproof flotation housing. In the event of capsize or other disaster, the beacon is turned on and thrown in the water. A signal is transmitted automatically from the beacon that is picked up by receiving stations on the shore. These stations typically would use antennas situated on high ground so as to provide maximum range coverage of coastal waters. The beacon frequency would be monitored continuously, so that a vessel in distress, so equipped would be detected almost immediately.
Advantageously, the modulation of the beacon signal would be sufficiently unique to allow prompt automatic verification that it comes from a vessel beacon transmitter. Once verified, a directional fix is obtained from the beacon and the coast guard or other rescue service informed. The beacon then can be used to guide the coast guard ship, helicopter or other vessel that is sent to the rescue. An efficient, inexpensive nautical emergency rescue system thereby is provided to the average pleasure boat owner.
The principal object of the present invention is to provide an inexpensive, efficient radio beacon for use with such a nautical emergency rescue system.
A particular problem associated with radio beacons is that of insuring efficient radiation with a transmitter of low power in a small package. Compact packaging, and the need for providing a signal that can be picked up from receivers situated in different directions precludes the use of a high gain directional antenna. Thus another object of the present invention is to provide a novel antenna configuration for a radio beacon.